jugad2 is Vasudev Ram's blog, tracking software innovation, both open source and proprietary, worldwide. I'm an independent developer with many years experience in many tech areas, and a Fellow at the Python Software Foundation. My biz site is www.dancingbison.com and I tweet @vasudevram .

(Only tried it from my Android mobile till now, and the Run button did not result in any output. Have to try it from a PC.)

Turtle graphics is only one way of giving training on the site, though. Anyone can host a course on the site for free.

I had first programmed turtle graphics in the LOGO programming language on my first home computer, an IBM PC Jr. It was fun. LOGO, a sort of simplified Lisp, was easy to learn and still fairly powerful. It's a good language to teach children programming.

Later, some time after first learning Python, I got to know that Python also has a turtle graphics module, which uses Tkinter, and tried it out.

Runestone, being web-based, probably uses the HTML5 canvas element.

Related links:

About Runestone Interactive:

http://interactivepython.org/courselib/default/about

Python turtle graphics module:

http://docs.python.org/2/library/turtle.html

Logo language on Wikipedia:

http://en.m.wikipedia.org/wiki/Logo_(programming_language)

Update: For kids (of all ages :-) interested in trying out LOGO, there are some free versions available.